This invention relates to sheet handling apparatus and is more particularly concerned with improvements in apparatus for automatically sorting and piling or stacking metal sheets thereby enabling piles or stacks of the sheets to be more conveniently handled during processing, storage or shipment.
Various machines with pile forming apparatus have heretofore been developed for handling metal sheets as they are delivered from a fabricating line or advanced in a processing line. Machines employed for this purpose are illustrated, for example, in U.S. Pat. No. 3,055,659 granted Sept. 25, 1962 and in U.S. Pat. No. 3,228,682 granted Jan. 11, 1966. In U.S. Pat. No. 3,055,659 sheets of magnetizable material are advanced on an overhead traveling belt conveyor, with the sheets held on the belt by electromagnets, and in U.S. Pat. No. 3,228,682 sheets of either magnetizable or non-magnetizable material are held on an overhead traveling belt conveyor by vacuum. Various arrangements have been provided in such machines for guiding the sheets onto a pile or stack. For example, such arrangments are illustrated in U.S. Pat. No. 3,111,311 granted Nov. 19, 1963 and in U.S. Pat. No. 3,711,087 granted Jan. 16, 1973. Some of the machines of this type have included multiple pile forming arrangements with provision for classifying which enables the sheets to be divided and piled in separate piles. One such arrangement is illustrated in U.S. Pat. No. 4,130,206 granted Dec. 19, 1978. While these machines and others of like character have served the purposes for which they have been designed, they have usually had some limitations particularly with respect to the type or character of the material which they are capable of handling. Consequently, there has been a need for an improved machine for this purpose which is capable of handling sheets of either ferrous or non-ferrous materials of various sizes and configurations, which is of simplified construction, which is easy to operate, which requires minimum maintenance, and which can be fabricated with substantial economy in the use of materials.
It is a general object of the invention, therefore, to provide an improved machine for handling a variety of metal sheets of ferrous or non-ferrous material and which may be economically built with provision for advancing sheets so that they may be divided into separate classes or groups and delivered to separate piling areas.
It is a more specific object of the invention to provide a sheet piling machine having an improved arrangement for classifying the sheets so as to enable dividing of the sheets for delivery to separate piling mechanisms with means at the classifying area for closing a gap between the discharge end of the infeed conveyor and a horizontal forwarding conveyor when selected sheets are to be advanced on the forwarding conveyor for delivery to one piling mechanism and for opening the gap while lowering the discharge end of the infeed conveyor to enable adequate clearance for rapid transfer of sheets to be delivered to another piling mechanism.
Another object of the invention is to provide in a machine of the type described, a sheet advancing conveyor having associated means for selectively discharging the sheets in two separate paths which are in vertically spaced relation and which lead to separate piling areas.
Another object of the invention is to provide in a machine of the type described an infeed conveyor having continuously traveling sheet supporting and conveying elements which are carried on rotating end support members mounted so as to provide a top path in a generally horizontal plane with the leading end normally positioned to deliver the sheets across a pivotally mounted gate to a carry-over conveyor, and with portions at the leading end of the infeed conveyor being swingable to a downwardly inclined position so as to permit selected sheets to be delivered, when the pivoted gate is raised, to a downwardly and forwardly inclined conveyor leading to a piling area, the pivoted end of the infeed conveyor serving to support and guide the sheets as they are advanced across the gate to the carry-over conveyor or beneath the gate to the downwardly inclined conveyor and the pivoted gate serving, when in normal position, to bridge the gap between the infeed and carry-over conveyors and, when swung to a raised position, to clear the entrance to the downwardly inclined conveyor.
A further object of the invention is to provide, in an apparatus of the type described wherein a leading portion of the infeed conveyor is swingable between a normal horizontal position and a downwardly inclined position, a tensioning arrangement for the traveling elements of the infeed conveyor which automatically maintains a predetermined tension in the traveling elements when the conveyor end is swung to the downwardly inclined position.
A still further object of the invention is to provide a piling machine for metal sheets wherein the sheets are fed to the machine on a traveling conveyor and selectively advanced to a piling area having end stop and back stop mechanisms with the back stop comprising a swivel arrangement with a passage for air to aid in the piling of the sheets.
To this end the invention as claimed herein is embodied in a machine which is adapted for piling metal sheets and which comprises a supporting frame having mounted thereon a sheet supporting and advancing conveyor having continuously traveling sheet carrying members mounted on longitudinally spaced rotatably mounted end support members with an intermediate support member for the top conveyor run which is spaced a predetermined distance from the support member at the discharge end of the conveyor, the end support member being mounted for hinged vertical movement between a raised position where the top conveyor run is horizontal and a lowered position so as to enable selected sheets to be advanced, when the end support member is in the raised position, across a pivotally mounted gate to a forwarding conveyor for delivery to a piling mechanism and when the end support member is lowered and the pivoted gate is swung upwardly to open the gap between the discharge end of the infeed conveyor and the forwarding conveyor so as to enable sheets to be delivered into the gap and to a downwardly directed ramp leading to a lower level piling area below the forwarding conveyor with means for automatically maintaining tension in the continuously traveling sheet support members.
The aforesaid objects and other objects and advantages of the invention will become more apparent when reference is made to the accompanying detailed description of the preferred embodiment of the invention which is set forth in the accompanying drawings wherein like reference numerals indicate corresponding parts throughout.